Registration pointer and method for registering a bone of a patient to a computer assisted orthopaedic surgery system

ABSTRACT

A registration pointer includes a camera located in an elongated shaft having a distal end configured to be contacted to a bone of a patient to register the bone to a computer assisted orthopaedic surgery system. The camera may be a hemispherical camera and may include a panoramic camera and a wide-angle camera equipped with a fish-eye lens. The registration pointer is configured to transmit images received by the cameras to the computer assisted orthopaedic surgery system for display thereon. The computer assisted orthopaedic surgery system may be configured to generate an image, such as a hemispherical image, based on the images received from the registration pointer.

This application is a divisional application of U.S. patent applicationSer. No. 11/428,078, filed on Jun. 30, 2006 and issued as U.S. Pat. No.7,885,701 on Feb. 8, 2011,which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates generally to computer assisted surgerysystems for use in the performance of orthopaedic surgical proceduresand, more particularly, to devices and methods for registering bones ofa patient to computer assisted surgery systems.

BACKGROUND

There is an increasing adoption of minimally invasive orthopaedicprocedures. Because such surgical procedures generally restrict thesurgeon's ability to see the operative area, surgeons are increasinglyrelying on computer systems, such as computer assisted orthopaedicsurgery (CAOS) systems, to assist in the surgical operation.

Computer assisted orthopaedic surgery (CAOS) systems assist surgeons inthe performance of orthopaedic surgical procedures by, for example,displaying images illustrating surgical steps of the surgical procedurebeing performed and rendered images of the relevant bones of thepatient. Before a computer assisted orthopaedic surgery (CAOS) systemcan display a rendered image of a bone, the bone must first beregistered with the computer assisted orthopaedic surgery (CAOS) system.Registering the bone with the computer assisted orthopaedic surgery(CAOS) system allows the system to determine the relevant contour,location, and orientation of the bone and display the rendered imageaccording to such parameters. In typical computer assisted orthopaedicsurgery (CAOS) systems, a bone is registered by touching a number oflocations on the surface of the bone with a tip of a registrationpointer. Based on a determined location of the registration pointer, thelocations of the surface of the bone are computed. The system may thengenerate a rendered image of the bone, including the contour of thebone, based on such computed locations.

SUMMARY

According to one aspect, a registration pointer for registering a bonewith a computer assisted surgery system may include an elongated shaft.The elongated shaft may have a distal end configured to be contacted tothe bone. For example, the distal end may include a lens manufacturedfrom an optical quality, industrial grade translucent gem-like materialsuch as quartz, ruby, diamond, and/or the like that is configured to becontacted to the bone. The registration pointer may also include acamera located in the elongated shaft. The camera may be, for example, ahemispherical camera and, in some embodiments, may include a firstcamera and a second camera. The first camera may be a panoramic cameraand/or the second camera may be a wide-angle camera. The panoramiccamera may have a horizontal field of view of about 360 degrees and avertical field of view of about 120 degrees when the elongated shaft ispositioned on a vertical plane. The wide-angle camera may have avertical field of view of about 60 degrees when the elongated shaft ispositioned on a vertical plane. The wide-angle camera may include afish-eye lens.

The registration pointer may also include a light source. The lightsource may be embodied as a light emitting diode located in theelongated shaft. Alternatively, the light source may be located outsidethe elongated shaft, such as in the handle of the registration pointer,and channeled into the elongated shaft via a suitable light conductorsuch as a fiber optic wire or cable. The registration pointer may alsoinclude a transmitter communicatively coupled to the camera andconfigured to transmit images received from the camera. The transmittermay be a wired or a wireless transmitter. The registration pointer mayalso include a button and a control circuit. The control circuit may becommunicatively coupled to the camera and the button. The controlcircuit may be configured to store an image received from the camera inresponse to selection of the button by a user of the registrationpointer.

According to another aspect, a computer assisted orthopaedic surgerysystem may include a registration pointer having a camera located at adistal end. The computer assisted orthopaedic surgery system may alsoinclude a display device and a processor communicatively coupled to theregistration pointer and the display device. The computer assistedorthopaedic surgery system may further include a memory deviceelectrically coupled to the processor. The memory device may have storedtherein a plurality of instructions, which when executed by theprocessor, cause the processor to receive a first image and a secondimage from the registration pointer. The first image and the secondimage may be received via a wired and/or wireless communication link.The plurality of instructions may also cause the processor to generate athird image based on the first image and the second image. The thirdimage may be, for example, a hemispherical image. Additionally, theplurality of instructions may also cause the processor to display thethird image on the display device. The display device may be a computerscreen, a display monitor, a heads-up display, and/or other type ofdisplay device. In some embodiments, the third image is superimposed ona rendered image of a bone.

In some embodiments, the camera may be a hemispherical camera. Thehemispherical camera may include a first camera and a second camera. Thefirst camera may be, for example, a panoramic camera. The second cameramay be, for example, a wide-angle camera having a fish-eye lens.Additionally, the plurality of instructions may cause the processor toreceive a signal from the registration pointer and store the third imagebased on the signal. The plurality of instructions may further cause theprocessor to receive position data indicative of a position of theregistration pointer and display a rendered image of a bone on thedisplay screen based on the position data.

According to yet another aspect, a method for displaying an image of apatient during the performance of an orthopaedic surgical procedure mayinclude receiving a first image from a camera of a registration pointer.The first image may be received from, for example, a panoramic camera.The method may also include receiving a second image from a secondcamera of the registration pointer. The second image may be receivedfrom, for example, a wide-angle camera having a fish-eye lens.Additionally, the method may include generating a hemispherical imagebased on the first image and the second image and displaying thehemispherical image on a display device. The method may also includeactivating a light source of the registration pointer. Further, themethod may include receiving a signal from the registration pointer andstoring the hemispherical image based on the signal.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description particularly refers to the following figures,in which:

FIG. 1 is a perspective view of a computer assisted orthopaedic surgery(CAOS) system;

FIG. 2 is a simplified diagram of the CAOS system of FIG. 1;

FIG. 3 is a perspective view of a bone locator tool;

FIG. 4 is a perspective view of a registration tool for use with thesystem of FIG. 1;

FIG. 5 is a perspective view of an orthopaedic surgical tool for usewith the system of FIG. 1;

FIG. 6 is a simplified diagram of another computer assisted orthopaedicsurgery (CAOS) system;

FIG. 7 is a perspective view of a registration pointer of the CAOSsystem of FIG. 6;

FIG. 8 is a side elevation view of a distal end of the registrationpointer of FIG. 7;

FIG. 9 is a simplified block diagram of an electrical circuit of theregistration pointer of FIG. 7; and

FIG. 10 is a simplified flow chart of an algorithm for registering abone of a patient to a computer assisted orthopaedic surgery system.

DETAILED DESCRIPTION OF THE DRAWINGS

While the concepts of the present disclosure are susceptible to variousmodifications and alternative forms, specific exemplary embodimentsthereof have been shown by way of example in the drawings and willherein be described in detail. It should be understood, however, thatthere is no intent to limit the concepts of the present disclosure tothe particular forms disclosed, but on the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the appended claims.

Referring to FIG. 1, a computer assisted orthopaedic surgery (CAOS)system 10 includes a computer 12 and a camera unit 14. The CAOS system10 may be embodied as any type of computer assisted orthopaedic surgerysystem. Illustratively, the CAOS system 10 is embodied as one or morecomputer assisted orthopaedic surgery systems commercially availablefrom DePuy Orthopaedics, Inc. of Warsaw, Ind. and/or one or morecomputer assisted orthopaedic surgery systems commercially availablefrom BrainLAB of Heimstetten, Germany. The camera unit 14 may beembodied as a mobile camera unit 16 or a fixed camera unit 18. In someembodiments, the system 10 may include both types of camera units 16,18. The mobile camera unit 16 includes a stand 20 coupled with a base22. The base 22 may include a number of wheels 21 to allow the mobilecamera unit 16 to be repositioned within a hospital room 23. The mobilecamera unit 16 includes a camera head 24. The camera head 24 includestwo cameras 26. The camera head 24 may be positionable relative to thestand 20 such that the field of view of the cameras 26 may be adjusted.The fixed camera unit 18 is similar to the mobile camera unit 16 andincludes a base 28, a camera head 30, and an arm 32 coupling the camerahead 30 with the base 28. In some embodiments, other peripherals, suchas display screens, lights, and the like, may also be coupled with thebase 28. The camera head 30 includes two cameras 34. The fixed cameraunit 18 may be coupled to a ceiling, as illustratively shown in FIG. 1,or a wall of the hospital room. Similar to the camera head 24 of thecamera unit 16, the camera head 30 may be positionable relative to thearm 32 such that the field of view of the cameras 34 may be adjusted.The camera units 14, 16, 18 are communicatively coupled with thecomputer 12. The computer 12 may be mounted on or otherwise coupled witha cart 36 having a number of wheels 38 to allow the computer 12 to bepositioned near the surgeon during the performance of the orthopaedicsurgical procedure.

Referring now to FIG. 2, the computer 12 illustratively includes aprocessor 40 and a memory device 42. The processor 40 may be embodied asany type of processor including, for example, discrete processingcircuitry (e.g., a collection of logic devices), general purposeintegrated circuit(s), and/or application specific integrated circuit(s)(i.e., ASICs). The memory device 42 may be embodied as any type ofmemory device and may include one or more memory types, such as, randomaccess memory (i.e., RAM) and/or read-only memory (i.e., ROM). Inaddition, the computer 12 may include other devices and circuitrytypically found in a computer for performing the functions describedherein such as, for example, a hard drive, input/output circuitry, andthe like.

The computer 12 is communicatively coupled with a display device 44 viaa communication link 46. Although illustrated in FIG. 2 as separate fromthe computer 12, the display device 44 may form a portion of thecomputer 12 in some embodiments. Additionally, in some embodiments, thedisplay device 44 or an additional display device may be positioned awayfrom the computer 12. For example, the display device 44 may be coupledwith the ceiling or wall of the operating room wherein the orthopaedicsurgical procedure is to be performed. Additionally or alternatively,the display device 44 may be embodied as a virtual display such as aholographic display, a body mounted display such as a heads-up display,or the like. The computer 12 may also be coupled with a number of inputdevices such as a keyboard and/or a mouse for providing data input tothe computer 12. However, in the illustrative embodiment, the displaydevice 44 is a touch-screen display device capable of receiving inputsfrom an orthopaedic surgeon 50. That is, the surgeon 50 can provideinput data to the computer 12, such as making a selection from a numberof on-screen choices, by simply touching the screen of the displaydevice 44.

The computer 12 is also communicatively coupled with the camera unit 16(and/or 18) via a communication link 48. Illustratively, thecommunication link 48 is a wired communication link but, in someembodiments, may be embodied as a wireless communication link. Inembodiments wherein the communication link 48 is a wireless signal path,the camera unit 16 and the computer 12 include wireless transceiverssuch that the computer 12 and camera unit 16 can transmit and receivedata (e.g., image data). Although only the mobile camera unit 16 isshown in FIG. 2, it should be appreciated that the fixed camera unit 18may alternatively be used or may be used in addition to the mobilecamera unit 16.

The CAOS system 10 may also include a number of sensors or sensor arrays54 which may be coupled the relevant bones of a patient 56 and/or withorthopaedic surgical tools 58. For example, as illustrated in FIG. 3, atibial array 60 includes a sensor array 62 and bone clamp 64. Theillustrative bone clamp 64 is configured to be coupled with a tibia bone66 of the patient 56 using a Schantz pin 68, but other types of boneclamps may be used. The sensor array 62 is coupled with the bone clamp64 via an extension arm 70. The sensor array 62 includes a frame 72 andthree reflective elements or sensors 74. The reflective elements 74 areembodied as spheres in the illustrative embodiment, but may have othergeometric shapes in other embodiments. Additionally, in otherembodiments sensor arrays having more than three reflective elements maybe used. The reflective elements 74 are positioned in a predefinedconfiguration that allows the computer 12 to determine the identity ofthe tibial array 60 based on the configuration. That is, when the tibialarray 60 is positioned in a field of view 52 of the camera head 24, asshown in FIG. 2, the computer 12 is configured to determine the identityof the tibial array 60 based on the images received from the camera head24. Additionally, based on the relative position of the reflectiveelements 74, the computer 12 is configured to determine the location andorientation of the tibial array 60 and, accordingly, the tibia 66 towhich the array 60 is coupled.

Sensor arrays may also be coupled to other surgical tools. For example,a registration tool 80, as shown in FIG. 4, is used to register pointsof a bone of the patient. The registration tool 80 includes a sensorarray 82 having three reflective elements 84 coupled with a handle 86 ofthe tool 80. The registration tool 80 also includes pointer end 88 thatis used to register points of a bone. The reflective elements 84 arealso positioned in a configuration that allows the computer 12 todetermine the identity of the registration tool 80 and its relativelocation (i.e., the location of the pointer end 88). Additionally,sensor arrays may be used on other surgical tools such as a tibialresection jig 90, as illustrated in FIG. 5. The jig 90 includes aresection guide portion 92 that is coupled with a tibia bone 94 at alocation of the bone 94 that is to be resected. The jig 90 includes asensor array 96 that is coupled with the portion 92 via a frame 95. Thesensor array 96 includes three reflective elements 98 that arepositioned in a configuration that allows the computer 12 to determinethe identity of the jig 90 and its relative location (e.g., with respectto the tibia bone 94).

The CAOS system 10 may be used by the orthopaedic surgeon 50 to assistin any type of orthopaedic surgical procedure including, for example, atotal knee replacement procedure. To do so, the computer 12 and/or thedisplay device 44 are positioned within the view of the surgeon 50. Asdiscussed above, the computer 12 may be coupled with a movable cart 36to facilitate such positioning. The camera unit 16 (and/or camera unit18) is positioned such that the field of view 52 of the camera head 24covers the portion of a patient 56 upon which the orthopaedic surgicalprocedure is to be performed, as shown in FIG. 2.

During the performance of the orthopaedic surgical procedure, thecomputer 12 of the CAOS system 10 is programmed or otherwise configuredto display images of the individual surgical procedure steps which formthe orthopaedic surgical procedure being performed. The images may begraphically rendered images or graphically enhanced photographic images.For example, the images may include three dimensional rendered images ofthe relevant anatomical portions of a patient. The surgeon 50 mayinteract with the computer 12 to display the images of the varioussurgical steps in sequential order. In addition, the surgeon mayinteract with the computer 12 to view previously displayed images ofsurgical steps, selectively view images, instruct the computer 12 torender the anatomical result of a proposed surgical step or procedure,or perform other surgical related functions. For example, the surgeonmay view rendered images of the resulting bone structure of differentbone resection procedures. In this way, the CAOS system 10 provides asurgical “walk-through” for the surgeon 50 to follow while performingthe orthopaedic surgical procedure.

In some embodiments, the surgeon 50 may also interact with the computer12 to control various devices of the system 10. For example, the surgeon50 may interact with the system 10 to control user preferences orsettings of the display device 44. Further, the computer 12 may promptthe surgeon 50 for responses. For example, the computer 12 may promptthe surgeon to inquire if the surgeon has completed the current surgicalstep, if the surgeon would like to view other images, and the like.

The camera unit 16 and the computer 12 also cooperate to provide thesurgeon with navigational data during the orthopaedic surgicalprocedure. That is, the computer 12 determines and displays the locationof the relevant bones and the surgical tools 58 based on the data (e.g.,images) received from the camera head 24 via the communication link 48.To do so, the computer 12 compares the image data received from each ofthe cameras 26 and determines the location and orientation of the bonesand tools 58 based on the relative location and orientation of thesensor arrays 54, 62, 82, 96. The navigational data displayed to thesurgeon 50 is continually updated. In this way, the CAOS system 10provides visual feedback of the locations of relevant bones and surgicaltools for the surgeon 50 to monitor while performing the orthopaedicsurgical procedure.

Referring now to FIG. 6, in another embodiment, a computer assistedorthopaedic surgery (CAOS) system 100 includes a controller 102 and aregistration pointer 104. The controller 102 is communicatively coupledto the registration pointer 104 via a communication link 106. Asdiscussed in more detail below in regard to FIG. 10, the communicationlink 106 may be embodied as any type of communication link capable offacilitating communication between the controller 102 and theregistration pointer 104. For example, the communication link 106 may bea wired communication link and embodied as any number of wires, cables,or the like. Alternatively, the communication link 106 may be a wirelesscommunication link. In such embodiments, the registration pointer 104may use any suitable wireless communication technology and protocol tocommunicate with the controller 102 via the communication link 106 suchas, for example, a Bluetooth wireless communication protocol, a wirelesslocal area network (WLAN) communication protocol, or the like.

The controller 102 includes a processor 108 and a memory device 110. Theprocessor 108 may be embodied as any type of processor including, forexample, discrete processing circuitry (e.g., a collection of logicdevices), general purpose integrated circuit(s), and/or applicationspecific integrated circuit(s) (i.e., ASICs). The memory device 110 maybe embodied as any type of memory device and may include one or morememory types, such as, random access memory (i.e., RAM) and/or read-onlymemory (i.e., ROM). In addition, the controller 102 may include otherdevices and circuitry typically found in a computer for performing thefunctions described herein such as, for example, a hard drive,input/output circuitry, and the like.

The controller 102 is communicatively coupled with a display device 112via a communication link 114. Although illustrated in FIG. 6 as separatefrom the controller 102, the display device 112 may form a portion ofthe controller 102 in some embodiments. Additionally, in someembodiments, the display device 112 or an additional display device maybe positioned away from the controller 102. For example, the displaydevice 112 may be coupled to the ceiling or wall of the operating roomwherein the orthopaedic surgical procedure is to be performed.Additionally or alternatively, the display device 112 may be embodied asa virtual display such as a holographic display, a body mounted displaysuch as a heads-up display, or the like. The controller 102 may also becoupled with a number of input devices such as a keyboard and/or a mousefor providing data input to the controller 102. However, in theillustrative embodiment, the display device 112 is a touch-screendisplay device capable of receiving inputs from the orthopaedic surgeon50 similar to the display device 44 described above in regard to FIG. 2.That is, the surgeon 50 can provide input data to the controller 102,such as making a selection from a number of on-screen choices, by simplytouching the screen of the display device 112.

Referring now to FIG. 7, the illustrative registration pointer 104includes a handle 120 and an elongated shaft 122 extending therefrom.The elongated shaft 122 includes a distal end 124 that is configured tobe touched or otherwise contacted to locations on a surface of a bone ofa patient during a bone registration procedure as described above inregard to FIG. 4. The distal end 124 includes a lens 126 having asubstantial hemispherical shape such that the geometric center of thelens 126 is approximately equidistant from each point on thehemispherical surface of the lens 126. As such, when the lens 126 iscontacted to a bone of a patient, the distance from the geometric centerof the lens 126 to the point of contact is approximately equalregardless of which point on the hemispherical surface of the lens 126is contacted with the bone. The lens 126 may be formed from anytransparent material having a substantial hardness such that the lens126 may be repeatedly contacted with bone and other tissue of a patientwithout substantially deteriorating the transparency of the material. Inone particular embodiment, the lens 126 is formed from crystal quartz.However, in other embodiments, other optical quality, industrial gradetranslucent gem-like material such as quartz, ruby, diamond, and/or thelike may be used.

A camera 128 is positioned in the elongated shaft 122 toward the distalend 124. The camera 128 is so positioned such that a field of view 130of the camera extends through the lens 126. As such, the registrationpointer 104 is usable to register bones of a patient to the controller102 in a manner as described above in regard to FIGS. 2 and 4 andprovide images of the relevant bone and other anatomical structures ofthe patient via the camera 128. The camera 128 may be embodied as anytype and number of cameras capable of being located in the registrationtool 104 and providing the desired image, field of view, etc. In oneparticular embodiment, the camera 128 is embodied as a hemisphericalcamera configured to produce a number of images from which ahemispherical image may be generated. For example, as described in moredetail below in regard to FIG. 8, the camera 128 may be embodied as apanoramic camera and a wide-angle camera.

The illustrative registration pointer 104 also includes a sensor array132 embodied as a number of reflective elements 134. The reflectiveelements 134 are substantially similar to the reflective elements 84illustrated in and described above in regard to FIG. 4. The reflectiveelements 134 are positioned in a predefined configuration that allowsthe controller 102 to determine the location and orientation of theregistration pointer 104 based on images received from the camera 16.

In other embodiments, other types of sensors may be used to determinethe location of the registration pointer 104. For example, in someembodiments, the registration pointer may include a magnetic orelectromagnetic source such as a permanent magnet. In such embodiments,the location of the registration pointer 104 may be determined based onsignals received from a number of magnetic sensors as described in moredetail in U.S. patent application Ser. No. 11/323,609, entitled“APPARATUS AND METHOD FOR REGISTERING A BONE OF A PATIENT WITH ACOMPUTER ASSISTED ORTHOPAEDIC SURGERY SYSTEM,” U.S. patent applicationSer. No. 11/323,963, entitled “SYSTEM AND METHOD FOR REGISTERING A BONEOF A PATIENT WITH A COMPUTER ASSISTED ORTHOPAEDIC SURGERY SYSTEM,” U.S.patent application Ser. No. 11/323,537, entitled “METHOD FOR DETERMININGA POSITION OF A MAGNETIC SOURCE,” and U.S. patent application Ser. No.11/323,610, entitled “MAGNETIC SENSOR ARRAY,” the entirety of each ofwhich is expressly incorporated herein by reference.

Additionally or alternatively, the registration pointer 104 may includea magnetic or electromagnetic sensor. In such embodiments, the locationof the registration pointer 104 may be determined based on the signalsreceived by the magnetic and/or electromagnetic sensors as described inmore detail in International Patent Application NumberPCT/GB2005/000874, entitled “Registration Methods and Apparatus,” and inInternational Patent Application Number PCT/GB2005/000933, entitled“Orthopaedic Operating Systems, Methods, Implants and Instruments”, theentirety of each of which is expressly incorporated herein by reference.As such, it should be appreciated that the sensor array 132 may beembodied a number of reflective elements, a number ofmagnetic/electromagnetic sensors, and/or a number ofmagnetic/electromagnetic sources such as permanent magnets. Accordingly,as used herein, the term “sensor array” is intended to refer to anynumber of reflective sensors, magnetic and/or electromagnetic sensors,and/or magnetic and/or electromagnetic sources.

The registration pointer 104 may also include any number ofuser-selectable input devices 136. For example, the registration pointer104 may include a button 136 selectable by a user of the registrationpointer 104 to capture or otherwise save an image received by the camera128 as discussed in more detail below in regard to FIG. 10. Althoughonly a single button 136 is illustrated in FIG. 7, it should beappreciated that in other embodiments the registration pointer 104 mayinclude any number of user-selectable input devices for controlling anyone or more functions of the pointer 104. For example, in someembodiments, as discussed below in regard to FIG. 8, the registrationpointer 104 may include a button or other input device selectable by auser of the pointer 104 to active a light source located in theelongated shaft 122 of the pointer 104. In embodiments wherein thecommunication link 106 is embodied as a wired communication link, theregistration pointer 104 may also include a cable, wire, or otherconductor 138 for communicatively coupling the pointer 104 to thecontroller 102.

As illustrated in FIG. 8, the registration pointer 104 also includes acontrol circuit 200. The control circuit 200 is located in the handle120 of the registration pointer 104 and is configured to control theoperations of the camera 128. The control circuit 200 includes aprocessor 202 and a memory device 204. The processor 202 may be embodiedas any type of processor including, for example, discrete processingcircuitry (e.g., a collection of logic devices), general purposeintegrated circuit(s), and/or application specific integrated circuit(s)(i.e., ASICs). The memory device 204 may be embodied as any type ofmemory device and may include one or more memory types, such as, randomaccess memory (i.e., RAM) and/or read-only memory (i.e., ROM).

The control circuit 200 is electrically coupled to the camera 128 via anumber of communication links 206 such as wires, printed circuit boardtraces, cables, or the like. In the illustrative embodiment, the camera128 is embodied as a hemispherical camera 208 and includes a panoramiccamera 210 and a wide-angle camera 212. As illustrated in FIG. 9, thecameras 210, 212 are located in the elongated shaft 122 and toward thedistal end 124 such that the field of view of each camera extendsthrough the lens 126. The panoramic camera 210 has a horizontal field ofview of about 360 degrees and a vertical field of view 214 of about 120degrees when the elongated shaft 122 of the registration pointer 104 islocated in a vertical plane 216 as shown in FIG. 9. The wide-anglecamera 212 includes a fish-eye lens and has a field of view 218 of about60 degrees. The fields of view 214, 218 are substantially contiguouswith each other in the illustrative embodiment. However, in otherembodiments, cameras having fields of view of different magnitudes. Insuch embodiments, the fields of view 214, 218 of each camera overlapeach other by a predetermined amount. Such overlap is calibrated orotherwise accounted for when generating the hemispherical image based onthe images received from each camera 210, 212 as discussed below inregard to FIG. 10.

Referring back to FIG. 8, the control circuit 200 is alsocommunicatively coupled to one or more input devices 220 via a number ofcommunication links 222. The communication links 222 may be embodied asany type of communication links, such as wires, cables, printed circuitboard traces, and the like, capable of facilitating communicationbetween the input devices 220 and the control circuit 200. The inputdevices 220 may be embodied as any type of input devices selectable by auser of the registration pointer 104. For example, the input device 220may be embodied as a button, such as the button 136 illustrated in FIG.7, a switch, or other device selectable by the user. Any number of inputdevices 220 may be included and may be selected by the user to provide arequest signal to the control circuit 200. For example, in oneembodiment, one of the input devices 220 is selectable by a user tocause the control circuit 200 to capture or otherwise store an imagereceived from the hemispherical camera 208. The image may be saved inthe memory device 204 of the control circuit 200 and/or the memory 110of the controller 102.

A transmitter circuit 224 is also included in the registration pointer104. The transmitter 224 is communicatively coupled to the controlcircuit 200 via a number of communication links 226. The communicationlinks 226 may be similar to the communication links 222 and may beembodied as any type of communication links, such as wires, cables,printed circuit board traces, and the like, capable of facilitatingcommunication between the transmitter circuit 224 and the controlcircuit 200. The transmitter circuit 224 may be embodied as any numberof electrical devices configured to transmit any number of imagesreceived from the hemispherical camera 208 to the controller 102 via thecommunication link 106. For example, the transmitter circuit 224 may bea wired transmitter configured to transmit the images over a wiredcommunication link 106. Alternatively, in embodiments wherein thecommunication link 106 is a wireless communication link, the transmittercircuit 224 may be embodied as a wireless transmitter and may use anysuitable transmission protocol, such as a Bluetooth communicationprotocol, a wireless local area network communication protocol, or thelike, to transmit the images from the registration pointer 104 to thecontroller 102.

In some embodiments, the registration pointer 104 may also include oneor more light sources 228. In such embodiments, the light sources 228are communicatively coupled to the control circuit 200 via a number ofcommunication links 230 such as such as wires, cables, printed circuitboard traces, and the like. The light source may be embodied as any typeof light source capable of producing enough light such that thehemispherical camera 208 (i.e., cameras 210, 212) is capable ofproducing images that may be viewed by a user. In one particularembodiment, the light source 228 is embodied a light emitting diode(LED), but other light emitting devices may be used in otherembodiments. As illustrated in FIG. 9, the light source 228 is alsolocated in the elongated shaft 122 and toward the distal end 124 suchthat light emitting from the light source 228 extends through the lens126.

In operation, the registration pointer 104 may be used by a surgeon orother healthcare provider during an orthopaedic surgical procedure toregister a bone of a patient with the controller 102. In addition, atany time during the surgical procedure, the surgeon may use theregistration pointer 104 to view the anatomy of the patient. To do so,the controller 102 may execute an algorithm 250 for displaying an imageof a patient during the performance of the orthopaedic surgicalprocedure. The algorithm 250 begins with process step 252 in which alight source is activated in the region desired to be viewed by thesurgeon. In embodiments wherein the registration pointer 104 includesthe light source 228, such as a LED, the light source 228 may beactivated in process step 252. To do so, the surgeon or other healthcareprovider may select the appropriate input device 220. In response, thecontrol circuit 200 is configured to activate the light source 228 via asignal supplied on the communication link 230. Alternatively oradditionally, the surgeon may activate the light source 228 or otherlight source by supplying the appropriate command to the controller 102via the display 112 (in embodiments wherein the display 112 is a touchscreen display) or via other input device(s) such as a keyboard. Inresponse, the controller 102 is configured to transmit a signal to theregistration pointer 104 via the communication link 106 to activate thelight source 228.

Next, in process step 254, images are received from the hemisphericalcamera 208 (i.e., from the panoramic camera 210 and from the wide anglecamera 212) and a new image, such as a hemispherical image, is generatedbased on such images in process step 256. The images from the cameras210, 212 may be received by the control circuit 200 and/or thecontroller 102. That is, in one embodiment, the control circuit 200 isconfigured to receive the images from the cameras 210, 212 and generatethe new image (e.g., a hemispherical image) based on the receivedimages. The generated image is subsequently transmitted to thecontroller 102 via the transmitter circuit 224 and the communicationlink 106. Alternatively, the control circuit 200 may be configured totransmit the images received from the cameras 210, 212 to the controller102 and the controller 102 is configured to generate the new image basedon the received images. Regardless, the images received from the cameras210, 212 are combined to generate a new image in the process step 256.In one particular embodiment, the new image is a hemispherical image,but in other embodiments, other types of images may be generated. Theimages received from the cameras 210, 212 may be combined to generatethe new image using any suitable algorithm. For example, in someembodiments, the images received from the cameras 210, 212 are appendedto each other. In such embodiments, the new image may include an amountof overlap or duplication of visible area. In other embodiments, theimages received from the cameras 210, 212 are combined in such a mannerthat any overlap or copy of the same visible area is reduced oreliminated from the new image. Yet further, in embodiments wherein onlya single camera is included in the registration pointer 104, a new imagemay or may not be generated based on the images received from the singlecamera. That is, the image received from the single camera may bedisplayed to the user of the system 100 as discussed below in regard toprocess step 260.

Next, in process step 258, the controller 102 determines if the user hasrequested to view the new image generated in process step 256. The usermay request to view the generated image by selecting a button displayedon the display 112 (in embodiments wherein the display is a touch screendisplay) or by providing a command via an input device coupled to thecontroller 102 such as a keyboard or mouse. Additionally oralternatively, in some embodiments, the input devices 220 of theregistration pointer 104 may include an input device 220, such as abutton or switch, that the user may select to view the generated image.In such embodiments, when the user selects the appropriate input device220, the control circuit 200 transmits a request signal via thetransmitter 224 and the communication link 106 to the controller 102.

If the user desires to view the generated image, the new image (e.g., ahemispherical image) is displayed to the user in process step 260. Thegenerated image is displayed on the display device 112. As discussedabove, in some embodiments, the display 112 is embodied as a heads-updisplay and the generated image is displayed thereon. The generatedimage may be displayed as a stand-alone image that the surgeon may useto inspect and/or navigate the anatomy of the patient. Additionally oralternatively, the generated image may be superimposed over the renderedimage of the patient's anatomy such that the rendered or calculatedanatomy (e.g., a bone) of the patient is comparable to the actualanatomy as displayed in the generated image.

Once the hemispherical image or other generated image(s) has beendisplayed in process step 260, the controller 102 determines if the userhas requested to capture or otherwise store the generated image inprocess step 262. The user may request to save the generated image byselecting a button displayed on the display 112 or by providing acommand via an input device coupled to the controller 102 such as akeyboard or mouse. Additionally or alternatively, in some embodiments,the input devices 220 of the registration pointer 104 may include aninput device, such as a button or switch, that the user may select tosave the generated image. In such embodiments, when the user selects theappropriate input device 220, the control circuit 200 transmits arequest signal to the controller 102 via the transmitter 224 and thecommunication link 106. In response, the controller 102 stores thegenerated image in process step 264. The generated image may be storedin, for example, the memory device 110 or in other storage devices suchas a hard drive or the like. Once stored, the generated image may beviewed by the surgeon and/or other healthcare provider at any time.

Once the image has been stored in process step 264 or if no request isreceived to display the image in process step 258 and/or to store theimage in process step 262, the algorithm 250 loops back to process steps254 wherein updated images are received form the cameras 210, 212. Inthis way, the algorithm 250 may loop through process steps 254, 256,258, and 260 to receive and display updated generated images based onthe updated images received from the cameras 210, 212 such that thestream of images form a video viewable by the surgeon. As the surgeonmoves or repositions the registration pointer 104, the generated imagesare updated and the surgeon may thereby use the video for inspectingand/or navigating the relevant anatomy of the patient.

While the disclosure has been illustrated and described in detail in thedrawings and foregoing description, such an illustration and descriptionis to be considered as exemplary and not restrictive in character, itbeing understood that only illustrative embodiments have been shown anddescribed and that all changes and modifications that come within thespirit of the disclosure are desired to be protected.

There are a plurality of advantages of the present disclosure arisingfrom the various features of the systems and methods described herein.It will be noted that alternative embodiments of the systems and methodsof the present disclosure may not include all of the features describedyet still benefit from at least some of the advantages of such features.Those of ordinary skill in the art may readily devise their ownimplementations of the systems and methods that incorporate one or moreof the features of the present invention and fall within the spirit andscope of the present disclosure as defined by the appended claims.

The invention claimed is:
 1. A registration pointer for registering abone with a computer assisted orthopaedic surgery system, theregistration pointer comprising: a handle, an elongated shaft extendingfrom the handle, the elongated shaft having a distal end configured tobe placed in contact with a bone of a patient, a panoramic camerapositioned at the distal end, a wide-angle camera having a fish-eye lenspositioned at the distal end, and a sensor array to provide anindication of a location of the registration pointer.
 2. Theregistration pointer of claim 1, further comprising a quartz crystallens located at the distal end of the elongated shaft.
 3. Theregistration pointer of claim 1, wherein the panoramic camera and thewide-angle camera form a hemispherical camera.
 4. The registrationpointer of claim 1, wherein the panoramic camera has a horizontal fieldof view of 360 degrees and a vertical field of view of 120 degrees whenthe elongated shaft is positioned on a vertical plane.
 5. Theregistration pointer of claim 1, wherein the wide-angle camera has avertical field of view of 60 degrees when the elongated shaft ispositioned on a vertical plane.
 6. The registration pointer of claim 1,further comprising a light source.
 7. The registration pointer of claim6, wherein the light source comprises a light emitting diode located inthe elongated shaft.
 8. The registration pointer of claim 7, wherein thelight source is a fiber optic light source.
 9. The registration pointerof claim 1, further comprising a transmitter communicatively coupled tothe panoramic camera and the wide-angle camera, the transmitter beingconfigured to transmit images received from the cameras.
 10. Theregistration pointer of claim 9, wherein the transmitter is a wirelesstransmitter.
 11. The registration pointer of claim 1, furthercomprising: an input device, and a control circuit communicativelycoupled to the panoramic camera, the wide-angle camera, and the inputdevice, the control circuit being configured to store an images receivedfrom one of the panoramic camera and the wide-angle camera in responseto selection of the input device by a user of the registration pointer.12. The registration pointer of claim 1, further comprising an inputdevice and a control circuit communicatively coupled to the inputdevice, the control circuit being configured to register a location ofthe bone in response to selection of the input device by a user of theregistration pointer.
 13. A registration pointer for registering a bonewith a computer assisted orthopaedic surgery system, the registrationpointer comprising: an elongated shaft, the elongated shaft having adistal end configured to be placed in contact with a bone of a patient,a sensor array to provide an indication of a location of theregistration pointer, and a hemispherical camera comprising a panoramiccamera positioned at the distal end and a wide-angle camera positionedat the distal end.
 14. The registration pointer of claim 13, wherein thewide-angle camera includes a fish-eye lens.
 15. The registration pointerof claim 13, further comprising a light emitting diode located in theelongated shaft.
 16. The registration pointer of claim 13, furthercomprising a transmitter communicatively coupled to the hemisphericalcamera and configured to transmit images received from the hemisphericalcamera.
 17. The registration pointer of claim 16, wherein thetransmitter is a wireless transmitter.
 18. The registration pointer ofclaim 13, further comprising an input device and a control circuitcommunicatively coupled to the hemispherical camera and the inputdevice, the control circuit being configured to store an image receivedfrom the hemispherical camera in response to selection of the inputdevice by a user of the registration pointer.
 19. The registrationpointer of claim 13, further comprising an input device and a controlcircuit communicatively coupled to the input device, the control circuitbeing configured to register a location of the bone in response toselection of the input device by a user of the registration pointer. 20.A registration pointer for registering a bone with a computer assistedorthopaedic surgery system, the registration pointer comprising: ahandle, an elongated shaft extending from the handle, the elongatedshaft having a distal end, a hemispherical camera positioned at thedistal end of the elongated shaft, the hemispherical camera comprising:a panoramic camera and a wide-angle camera having a fish-eye lenspositioned at the distal end, a quartz crystal lens positioned at thedistal end of the elongated shaft, the quartz crystal lens beingconfigured to be placed in contact with a bone of a patient and beingpositioned such that each of the panoramic camera and the wide-anglecamera have a field of view extending through the quartz crystal lens,and a sensor array to provide an indication of a location of theregistration pointer.